This invention relates to apparatus and methods for joining bones or repairing bone fractures and, more particularly, to means and methods employing a pin or shaft passing through an aperture in the bone or bones which is held in place by a self-locking button.
Trauma to human and animal bones is common. The trauma may occur as a result of accident or may be the result of some surgical procedure which requires portions of the bones to be removed or altered. The damaged bones may be broken through or merely partially fractured.
Healing of the damaged bones is greatly improved if the portions to be rejoined can be tightly clamped together. Since the process by which bone cells on either side of the break knit together is comparatively slow, the clamping of the bones must usually extend over a period of many days, often months.
Many techniques have been used in the past to keep the damaged bones clamped together. External casts, braces, and splints are familiar examples. Under many circumstances, such methods allow considerable movement of the bones and are less effective than is desired. More recently, internal clamps in the form of screws and pins have also been utilized. Screws may not be useful if the bones are particularly fragile and prior art clamps are often mechanically complex and difficult to properly install. Thus, there is a continuous need for improved bone clamps and bone clamping methods in order to provide more effective ways of immobilizing the damaged portions of human and animal bones during healing.
Accordingly, it is an object of the present invention to provide an improved means and method for clamping bones.
It is a further object of the present invention to provide an improved means and method for clamping bones wherein a clamp having fewer and simpler parts is provided.
It is an additional object of the present invention to provide an improved bone clamp and method wherein the clamp can be inserted through an aperture in one or more bones and locked firmly in place.
It is a further object of the present invention to provide an improved bone clamp and method wherein the clamp on being pressed together automatically locks tightly against the bone without further assembly.
It is an additional object of the present invention to provide an improved bone clamp and method consisting of only two parts, a through pin and a clamp button which automatically locks to the pin.
It is a still further object of the present invention to provide an improved clamp and method employing a pin and clamp button having a circumferential ratchet-type latching mechanism.
A copending invention by the same inventor entitled "Bone Handling Apparatus and Method", Ser. No. 776,772, now U.S. Pat. No. 4,688,561, gives additional details of the problem of clamping bones and use of bone clamps and is incorporated herein by reference.